Depart for Lac de Casterino for a hike in the mélézin along the river. Keep an eye out for the brown-and-white dipper, a small passerine bird that always stays close to the water.
From the Casterino information point, cross the footbridge and then take the track which climbs for about 100 metres to marker 368.
Then follow the signs for Baisse d'Ourne. A wooden fence closes the path; go around it to the right.
The path then skirts several private properties bordered by meadows and leads to marker 366. Continue straight ahead: the track descends slightly and approaches the river.
Follow the path to the lake.
Return by the same route.